“The quantum theory of parallel universes is not the problem, it is the solution. It is not some troublesome, optional interpretation emerging from arcane theoretical considerations," says David Deutsch. "It is the explanation, the only one that is tenable, of a remarkable and counter-intuitive reality. Everything in our universe -- including you and me, every atom and every galaxy -- has counterparts in these other universes."
In his book The Fabric of Reality, Deutsch laid the groundwork for an all-encompassing Theory of Everything by tying together four mutually supporting strands of reality: First: Hugh Everett's many-worlds interpretation of quantum physics, "the first and most important of the four strands"; second: Karl Popper's epistemology, especially its requiring a realist interpretation of scientific theories, and its emphasis on being falsifiable; third: Alan Turing's theory of computation, replaced by Deutsch's universal quantum computer; and fourth: Richard Dawkins' neo-Darwinian evolutionary theory and the modern evolutionary synthesis.
"Our best theories are not only truer than common sense, they make more sense than common sense," Deutsch wrote about the most mind-bending aspects of particle physics, including the tendency of matter to exist in more than one place at a time.
In the TED Conference video below filmed at Oxford University, Deutsch will force you to reconsider your place in the world, and about our species' significance in the universe. Far from being simply "chemical scum," quoting Stephen Hawking, we have the ability to gain knowledge, the importance of which, he says, is that we are always equipped to solve problems (including global warming). The brain contains the tools we need: knowledge, reason and creativity. It's a thrilling, and much needed, profoundly optimistic argument.